The present invention relates to a portable lock. More particularly, the present invention relates to a portable lock with a housing and a locking member, the locking member releasable from a locked position via at least an electronic actuator.
It is commonly known that when an individual is concerned about maintaining articles in a secure environment, people routinely use a variety of locking devices to secure receptacles wherein the material to be safeguarded is retained, such as, for example, safety deposit boxes and lockers. In such settings individuals utilize padlocks of either the key or combination variety on the latches of these containers so as to maintain the contents in a secure fashion. Standard padlocks widely available today consist of three basic types: 1) A standard key lock which operates on the basis of a tumbler system and is actuated by inserting a key into a cylinder at the base of the lock which contains pins or mechanical devices which release a locking bar mechanism when the key is turned. 2) A standard combination padlock which is is operated by rotating a numbered dial on the front of the lock body. Attached to the dial internally, is a series of disks which have stops and open gaps cut out such that they are aligned to all be in the same open position by rotation of the dial in both directions based upon a pre-programmed set of numbers derived from a factory which produces the lock. According to this type of lock, once the aforementioned spaces are aligned in the open position, the lock can be opened by pulling down on the lock body. 3) A standard combination padlock which is operated by turning a series of numbered tumblers to a pre-set combination which aligns gaps in a locking bar to an open position. Once this open position is achieved, the lock is free to disengage when the lock body is pulled away from the locking bar. These types of locks have been available for a considerable period of time. However, unless the user has the key or is able to remember the factory-provided combination, it is not possible to open these locks. Further, it is not possible to change the method by which these locks may be opened.
In response to the foregoing and other problems, various electronic locks and lock-boxes incorporating padlocks have been developed. One example of an electronic door lock is “Self-Contained Electromechanical Locking Device”, U.S. Pat. No. 4,901,545 to Bacon, which teaches an electromechanical lock incorporated into a doorknob for use on an original installation of a door lockset, or for retrofitting onto an existing door lockset. The lock in Bacon is characterized by a doorknob having the usual key-cylinder and tumbler mechanism. Additionally, Bacon comprises a keypad mounted on the top of the doorknob and connected to a computer controller housed within the knob. In turn, the controller is operably connected to a motor also housed within the knob. The motor moves a locking pin, which resides within an aperture adjacent the tumbler mechanism, between a locked and unlocked position. (See Item 65, FIG. 6 and Col. 5, Line 62-Col 6, Line 18). When a correct key-code is entered, the locking pin moves out of engagement with the tumbler mechanism, thereby allowing a key or a turn-key to turn in the key-hole and thus open the lock. Unfortunately, the mechanical linkage of the motor to the tumbler mechanism requires a bulky housing, which is suitable for a door lockset but unsuitable for a padlock, and the small locking pin in Bacon is unsuitable for securing a shackle in a padlock. Further, the lock in Bacon essentially has a two-stage unlocking procedure; first, the key-code must be entered, and second, the key must be turned within the lockset. This two-stage procedure saves battery life by reducing power consumption, but is thus unsuitable for a lock with a one-stage unlocking procedure.
Another example of a lock is found in “Gearshift Lock”, U.S. Pat. No. 5,561,996 to Chang, which teaches a large padlock that prevents a gearshift from moving out of the park position, thereby preventing theft of the vehicle. The lock in Chang incorporates a lock box having two parallel passages to receive each end of a U-shaped shackle. The shackle has a recess on each end for locking engagement with the box. The lock box incorporates a locking mechanism which engages the recesses when the shackle is inserted within the passages. The locking mechanism embodies a motor having a pinion gear on its output shaft. The top of the pinion gear engages an upper rack gear, while the bottom of the pinion gear engages a lower rack gear. Each rack gear is “L” shaped, having a bar mounted perpendicularly on their ends. The rack gears are biased away from each other by a pair of springs, which drive the bars into the recesses. A mechanical key is used to activate a switch to drive the motor in a reverse (unlocking direction) which compresses the springs and urges the rack gears together. The motor is powered by the vehicle battery. It will be apparent to those of skill in the art that the rack gears and springs must be of a sufficient size to resist attempts to break the lock and, accordingly, a relatively large motor and power supply is required to generate sufficient torque to compress the springs and move the rack gears.
When driven in the reverse direction, the upper and lower rack gears are driven inwards, thus disengaging the bars from the recesses, thereby releasing the shackle from the lock box. While the lock in Chang is suitable for a large gearshift lock having an external power source, it is unsuitable for a small padlock requiring a self-contained power supply. Further, the lock in Chang requires the use of a key, and cannot be operated by simply entering a combination or key-code.
“Electronic Access Card Having Key Pads and Coils and Combination Using the Same”, U.S. Pat. No. 4,864,115 to Imran and Clark, teaches an electronic access card that can be used to operate real estate agent lock boxes which retain a door key. Such boxes are typically combined with a padlock for securing the box to a doorknob, and are used to give several real estate agents access to a single door key of a dwelling, by affixing the lock box to an outside door of the dwelling. The access card contains a power supply and a plurality of programming features to allow the card to open multiple lock boxes, and to record and limit access time to the lock boxes.
“Electronic Lock Box, Access Card, System and Method”, U.S. Pat. No. 4,851,652 to Imran, teaches a type of real estate agent lock box for retaining a door key combined with a padlock for securing the box to a doorknob. Imran includes an external electronic key, which houses a power supply for operating both the lock box and the padlock. Electromagnetic solenoids are used to move leaf springs to open the lock box and the padlock. It will be apparent to those of skill in the art that springs of sufficient size must be used in order to keep the box secured.
“Improved Electronic Security System”, WO 93/03246 to Babler, teaches an electronic lock box for storing a mechanical key combined with a padlock for affixing the box to a doorknob. The lock box has a nest on its exterior to receive an electronic key. The lock box further includes an interior computer, an internal locking mechanism for the lock box, and an internal locking mechanism for the padlock. The padlock locking mechanism within the lock box includes a solenoid having a pair of plungers which are spring biased in an outward position to engage the shackle, and can be retracted by an electromagnetic winding within the solenoid to release the shackle.
The external electronic key has a keypad, a computer and a power supply to power both the electronic key and the lock box. To use the electronic key, it is inserted into the nest at which point the computer in the keypad communicates with the keypad in the lock box to establish a combination. At this point the real estate agent can use the keypad to enter a combination to either open the lock box or the shackle. The power to engage and disengage the locking mechanism is provided by batteries located within the external electronic key. While Babler is well suited to the needs of real estate agents, the lock box in Babler is not suitable for use as a simple Us padlock as the power supply and electronic key are not self-contained within the lock box. Furthermore, the combination of the lock box is not programmable within a self-contained unit.
“Electronically Controlled Security Container for Retaining Door Key”, U.S. Pat. No. 5,791,172 to Deighton, teaches another type of real-estate electronic lock box combined with a padlock. The padlock shackle has a notched arm which engages a fork member pivotally mounted on the container chassis. The fork member is urged by a spring in a direction for disengagement but is retained in engagement by a cam which engages a second tapered wheel connected to the motor gear train. When the motor is driven in a certain direction, the cam is driven along the wheel and finally off the end thereof, permitting the fork to be driven out of engagement with the shackle arm. It will be apparent that the padlock in Deighton is not intended to secure a door shut, but only to retain the lock box on a door handle and, accordingly, in order to adapt Deighton for use as a padlock, a sufficiently large spring biasing device would be necessary to adequately secure the shackle. This is disadvantageous, because a large spring would require a larger motor and self-contained power supply in order to operate the lock. Deighton also incorporates an infrared key and lock actuation system, which is disadvantageous as the key could be lost.
“Electronic Secure Entry System Apparatus and Method”, U.S. Pat. No. 4,609,780 to Clark, teaches another type of real-estate electronic lock box combined with a padlock. A notched shackle having a spring-biased latching member normally engaging the notch can be retracted from the notch with an electromagnetic solenoid, thereby releasing the shackle. A keypad connected to an electronic control board engages the solenoid when the correct keycode is entered into the keypad. However, similar to other prior art, the latching member must be sufficiently sized to prevent the shackle from opening thereby necessitating a larger spring and solenoid, and thus requiring the lock box to be of sufficient size to house the entire mechanism and power supply.
“Electronic Lock”, WO 90/15910 to Symons, teaches an electronic lock having a notched shackle engaged by a pair of rods spring-biased outwardly to engage the notches. An electromagnetic solenoid can be activated to retract the rods inwardly, thereby releasing the shackle. Symons has the same disadvantages as other prior art, namely that a spring of sufficient size must be used to ensure the rods securely engage the shackle, thereby necessitating a sufficiently large solenoid and power supply to overcome the force of the springs.
“Locking Devices”, GB 2 144 483 A to Miller et al., teaches two embodiments of an electronic padlock, both of which incorporate a rod which is spring biased to engage a recess in the shackle. Miller incorporates a solenoid or winding to compress the spring and retract the rod from the recess in the shackle. Unfortunately, the use of a spring necessitates a sufficiently sized power supply and solenoid to overcome the force of the spring. Accordingly, the power supply in Miller is external to the padlock, and is incorporated into an external key-device. Further, due to the constraints of batteries, this padlock is not suitable to a key-less, self-contained padlock having a long battery life between battery changes. Finally, the use of solenoids necessitates a shorting bridge to prevent false actuation by a powerful external magnet.
Each of these documents are incorporated fully by reference herein.